[Dual Function]: Can be used as a door stop alarm and door stopper, Its high damping rubber bearing can prevent the door sliding and prevent the bad guys into. Can be used in home and travel.,[3 Level of Sensitivities]: High-Medium-Low Sensitivities, you can adjust according to the gap between your door and floor and the type of flooring. Security door stopper alarms are suitable for clearances of 0.6" and 1.2" between the door and the ground.,[Loud Alarm]: The door stoppers alarm in the "ON" status, once someone tries to break in, the door stopper will obstruct and make a loud alarm with 120 dB (volume can not be adjusted) to alert.The doorstop alarm will provide you with safety when traveling or on business.,[Powered by 9V Battery]: The door stopper with alarm powered by 9V battery, One piece can be used for a year under normal circumstances. When the sound fades or disappears, replace the battery. (Note: Battery not include),[Easy to Use]: No installation required, Simply place the door alarm behind any inner pull door(For inward-opening doors only). Small size, light weight, very convenient to take with you when travel or stay indoor alone. The weight is only 4.5 ounces.